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  <title>Document</title>
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  <script>

    function Star(uname,age) {
      this.uname = uname
      this.age = age
    }

    const zjl = new Star('周杰伦',18)
    console.log(zjl.__proto__ === Star.prototype); //true
   console.log(Star.prototype.constructor === Star); //true

   console.log(zjl.__proto__.__proto__ ===Object.prototype); //true
   console.log(Object.prototype.constructor === Object); //true
   console.log(zjl.__proto__.__proto__.__proto__); //null

  </script>
</body>
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